ENS Event | |
|---|---|
05:11 Nov 3, 2020 | |
| Title | Both Trains of Salt Water Inoperable |
| Event Description | At 0011 EST on 11/03/20, it was discovered that BOTH trains of salt water were simultaneously INOPERABLE. While in a planned [limiting condition for operation] LCO window with the 21 salt water train INOPERABLE for post-maintenance testing, debris intrusion in the 22 salt water header rendered the redundant salt water train INOPERABLE.
Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). One train of salt water was restored to operable at time 0026 EST. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. This event did not affect Unit 1.
Following the eight hour 10 CFR 50.72 notification made on 11/03/2020 (EN 54979), further engineering analysis determined that 22 Saltwater subsystem flow remained at levels sufficient to fulfill its safety function based on the conditions existing at the time of the event. Despite flow in 22 Saltwater subsystem falling below the short term (four hour) minimum value for approximately 15 minutes, engineering analysis was able to determine the increased heat removal capacity associated with the lower bay temperatures was sufficient to offset the reduced heat removal capacity associated with the lower 22 Saltwater subsystem flow. This demonstrated that actual heat transfer to the saltwater subsystem was sufficient to ensure all safety functions were fulfilled during the event. Therefore, this event notification is being retracted as it is not reportable pursuant to 10 CFR 50.72(b)(3)(v)(A), (B) and (D). The NRC Resident has been informed. Notified R1DO (Greives) |
| Where | |
|---|---|
Calvert Cliffs  Maryland (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor | |
| Time - Person (Reporting Time:+2.82 h0.118 days <br />0.0168 weeks <br />0.00386 months <br />) | |
| Opened: | John Singleton 08:00 Nov 3, 2020 |
| NRC Officer: | Jeffrey Whited |
| Last Updated: | Nov 20, 2020 |
| 54979 - NRC Website
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Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 549792020-11-03T05:11:0003 November 2020 05:11:00
[Table view]10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor Both Trains of Salt Water Inoperable 2020-11-03T05:11:00 | |